/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.iotdb.db.wal.buffer;

import java.util.concurrent.TimeUnit;

/**
 * This class serializes and flushes {@link WALEntry}. If search is enabled, the order of search
 * index should be protected by the upper layer, and the value should start from 1.
 */
public interface IWALBuffer extends AutoCloseable {
    /**
     * Write WALEntry into wal buffer.
     *
     * @param walEntry info will be written into wal buffer
     */
    void write(WALEntry walEntry);

    /**
     * Get current log version id
     */
    long getCurrentWALFileVersion();

    /**
     * Get current wal file's size
     */
    long getCurrentWALFileSize();

    /**
     * Get current search index
     */
    long getCurrentSearchIndex();

    @Override
    void close();

    /**
     * Wait for next flush operation done
     */
    void waitForFlush() throws InterruptedException;

    /**
     * Wait for next flush operation done
     */
    boolean waitForFlush(long time, TimeUnit unit) throws InterruptedException;

    /**
     * Return true when all wal entries all consumed and flushed
     */
    boolean isAllWALEntriesConsumed();
}
